These additional parts are offered here so that groups with instrumentation different from the basic Real 'Cool' Book will still be able to play these charts. So if your group doesn't have a trumpet player, for example, we have here the same part (or very close) written for alto sax, for flute, and also for vibes. Each of these books are, of course, transposed for the key of the instrument playing it.

These parts could also be used as additional parts that double the original part. So for instance both a trumpet and vibes could play Part 1 together.

Be careful when it comes to the solo sections, however. If you are an alto player playing the Part 1 (trumpet) part, do not solo on the Alto solo sections, but rather on the Part 1 solo sections. This should become clear once you have looked the parts over. Enjoy!